Security steel guards having steel bars and hinged over a door or window opening or the like have been used for many years to discourage unauthorized entry. In the past, hasps and slide bolts were provided for use with a padlock and this design has given way to integral tamper-proof bolt locks which may be keyed to use the same key as the normal door. A significant development has been applicant's invention of a multiple piece adjustable security gate which is suitable for installation in doors having widths varying from twenty-eight inches to thirty-eight inches or more. Applicant's gate has been patented under U.S. Pat. No. 4,026,070, the disclosure of which is incorporated herein by reference.
While the development of hinged protective guards having locks has increased the applications and numbers of installations for security guards, there has been a growing concern about the need to quickly and easily open these devices in the case of an emergency. For example, if a fire were to break out in a home having security guards installed and locked in place, it would be important to be able to quickly and easily open the security guards. This may be accomplished with present designs by having duplicate keys stored near each guard and readily accessible for use in emergencies. However, some municipalities have begun to insist on keyless locking mechanisms which permit the opening of security guards without having to search for a key or the like. A security guard which provided these features would allow the rapid and easy exit from a home while still affording substantially increased protection from the entry of burglars, prowlers and other persons with nefarious intent.
There have been several attempts in the prior art to solve this problem but these devices have been generally expensive to install and weaken the security provided by the guard. One of these devices includes a hinged security guard with a keeper having a spring and keyway welded to the frame, opposite the hinge. A rod is mounted and extends through the window casing or door jamb and wall and has a key which extends into the keyway of the keeper and is rotated to secure the guard in the closed position. An operating handle is attached to the inside end of the rod and may be used to turn the rod to open and close the guard. As is evident, it can be very expensive to install an operating rod through a wall and window casing or door jamb, especially when the device must be suitable for use with the wide variety of wall construction found in various parts of any community. For example, the wall may be a concrete basement wall, a simple two by four and plaster board wall, a full brick and plaster wall, etc. Some of these types of construction are particularly unsuited to the installation of such an operating rod. Another problem with this design is that all one need to do to gain entry is reach through the bars of the guard and turn the operating handle. Anyone making a casual visual inspection of the guard could easily determine that an operating handle is there and it would not be difficult to figure out its function.
Another type of prior art device is somewhat improved but still exhibits drawbacks which limit its usefulness. This device is described in a brochure and includes a pair of latch and cable releases with a wall mounted foot pedal operator. Although the details of this device are somewhat vague, they include a safety release which is mounted to the outside wall and a pair of operating cables which extend through the wall and into a cable channel mounted on the interior wall. The operating cables extend parallel to the window casing and down to the wall mounted foot release which is near the bottom of the wall and directly below the cable channel. The release mechanism is not described in detail but fits into a receptacle on the window guard and holds it in a closed position. Two release mechanisms are provided per guard. The safety release may be operated by pushing the foot release which apparently retracts the cable and operates the release to pop open the guard, although this is not completely explained in the publication. This design has several drawbacks which limit its usefulness. For example, the cable must extend through the wall and must be extremely flexible to make a 90.degree. radius within a short distance as it enters the cable channel mounted to the interior wall. This sharp 90.degree. turn provides a rapid wearing point for the cable resulting in a frayed or broken cable and also could create the possibility of the cable jamming or hanging up. This also increases the adjustment problems over the life of the cable release as a frayed or worn cable has an increased tendency to stretch during use. Although details of the catch mechanism are not disclosed, it is apparent that it does not allow for a significant amount of tolerance to accommodate this expected variance in cable length. This problem is exacerbated by the use of two releases on a single guard whose cable lengths must be matched during installation with the travel of the foot release. Variances in adjustment between these two releases would almost inevitably occur, causing one release to operate and the other to hang up and thus prevent the guard from being opened. The foot release as disclosed is mounted on the wall which increases the installation problems due to the wide variability of materials used to construct interior walls. As mentioned above, anything from plaster board to brick and mortar may be used and some of these materials are particularly unsuited to screw type mounting as disclosed with this foot release. Furthermore, the mounting position of the foot release and the lack of a protective shield make it readily accessible through the window.
Applicant has succeeded in developing a quick release device which provides for the convenient opening of a security guard without a key, without sacrificing any of the protective benefits and without an expensive and difficult installation. Applicant's invention may be quickly and easily installed in new or existing security guards which are mounted either outside the opening or inside the opening with hinges providing either outward or inward movment of the guard when released. Applicant's cable release consists essentially of a spring loaded plunger which is swedged into the outer frame of the guard and an armored cable connected thereto and extending to a foot treadle having a shield thereon. A keeper is provided in a striker bar mounted to a door jamb or window casing which matches and lines up with the spring loaded plunger. The armored cable and spring loaded plunger are mounted in the hinged guard and sufficient length of cable may be provided to allow free movement of the guard about the hinges. The cable may be threaded through the openings between the bars in the guard and thus is easily adaptable for either an inward swinging guard or the conventional outwardly swinging guard.
Another unique feature of applicant's device is that if the armored cable is cut by one seeking to gain unauthorized entry, the spring loaded plunger would be driven home within the keeper and the flexible cable within the armored housing would withdraw inside the housing and be inaccessible. It would be necessary to peel back the armoring to gain access to the flexible cable. However, the average burglar would be stymied and would give up his attempt to gain access. It should also be noted that the armoring of the cable in applicant's preferred embodiment makes it much more difficult to cut than the actual steel bars of the guard. Thus, applicant's cable may tend to attract a burglar's attention away from the weaker part of the guard which increases the effectiveness of the guard itself.
Another advantage of applicant's invention is that if the cable is damaged, replacement thereof would be relatively easy compared with the problems of replacing the through-the-wall installations in the prior art. Burglary attempts could cause substantial damage to an owner's walls or windows and doors whereas with applicant's device, the burglar's attention is drawn to the loose cable which may be mounted completely outside of the surrounding structure.
The shielded foot treadle operator which applicant uses to operate the cable release is designed for floor mounting which has significant advantages over the wall mounted device of the prior art. For example, almost all floors are either wood or concrete which are easily adaptable for screw type mounting. Furthermore, if a carpet covers the flooring, applicant's device may be installed and removed without significant adverse effects on the appearance of the carpeting. The carpeting pile has a tendency to regain its shape and will actually conceal the screw holes made to install applicant's foot treadle. The shield for the foot treadle avoids the problem of the prior art device in that if mounted correctly, it is virtually impossible to reach through the security guard and operate the foot treadle. Also, with applicant's foot treadle mounted on the floor, small children may easily operate the cable release by using the weight of their bodies and the muscles in their legs which are the strongest muscles a youngster has. Thus, applicant's device provides for increased security with maximum convenience and safety for those installations requiring immediate opening of security guards without the use of a key.
These and other features of applicant's device may be more fully understood by referring to the drawings and description of the preferred embodiment.